Screw having a slotted head and a driving tool therefor



Aug. 28, 1951 M. DADERKO, sR.. ET AL 2,565,055

SCREW HAVING A SLOTTED HEAD AND A DRIVING TOOL THEREFOR Filed July 19, 1948 Michael Dada/k0, 5r. Robert A. Lise/la John Daderko zzvmvroxs.

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Patented Aug. 28, 1951 p SCREW HAVING A SLOTTED HEAD AND A DRIVING TOOL THEREFOR Michael Daderko, Sr., and Robert A. Lisella, summit Hill, and John Daderko, Coaldale, Pa.

Application July 19, 1948, Serial No. 39,424

3. Claims. (Cl. 145-50) This invention relates to a screw having a Another object is to prevent the screw from slipping endwise while mounted on the driving tool.

A still further object is to enable the screw to be utilized with the conventional screw driver without in any way requiring alteration of the v screw or the screw driver.

The above and other objects may be attained by employing this invention which embodies among its features a screw including a threaded stem, a head at one end of the stem, said head having a groove extending transversely there across and opening through the top thereof, said groove intersecting the axis of the stem with its bottom wall lying substantially perpendicular to said stem, the side walls of the groove being undercut as they approach the bottom of the groove, said side walls having opposed concave recesses therein substantially midway between opposite ends thereof and the bottom ends of the recesses coinciding with the bottom of the groove.

Other features include a driving tool for said screw including a shank, a bit on the shank, opposite faces of said bit being substantially flat and converging as they recede from the shank to form a relatively thin end edge, a lip on the bit extending laterally from one face thereof at the end remote from the shank, said lip being adapted to enter the undercut in one side wall of the groove in the screw head, a convex stop on the bit extending longitudinally along the face thereof remote from that from which the lip projects, and said stop being located substantially midway between opposite ends of the end edge of the bit for entrance into a concave recess in the screw head to hold the screw against longitudinal movement of the lip when the screw is mounted on the driving tool.

In the drawings:

Figure 1 is a perspective view of a screw driving tool embodying the features of this invention showing a screw embodying the features of this invention mounted thereon ready for insertion in the work;

Figure 2 is an enlarged fragmentary side view of the screw and driving tool assembled, illus- Figure 4 is an end view of Figure 3; and

Figure 5 is an end view of the screw illustrated in Figure 2.

Referring to the drawings in detail a screw designated generally Ill comprises a shank 12 which is threaded in a conventional manner and provided at one end with a head l4. The head I 4 of the screw I0 is provided with a transversely extending slot or groove commonly known as a kerf, the bottom wall It of which lies perpendicular to the longitudinal axis of the stem 12 and intersects said axis substantially midway between opposite ends. The side walls of the slot or groove extend toward the end of the head [4 and are undercut adjacent the bottom [6 as at H3, or the groove may be of general dovetail cross section according to the choice of the user. Asshown the groove opens through the end of the screw head I4 remote from the stem I 2 and formed in opposite side walls of the groove and opening outwardly through the end of the screw head l4 remote from the stem trating in broken lines the manner in which the driving tool may be removed from the screw;

Figure 3 is a side view of the bit of the driv- 1 g tool;

12' are concave recesses 20 which in the preferred form of the invention lie directly opposite one another and symmetrical about the axis of the stem I2. The inner ends of the recesses lie coincident with the bottom I6 of the groove as will be readily understood upon reference to Figure 2. 7

Obviously the screw above described may be utilized with a screw driver having a conventional bit but in order to achieve the greatest utility of this invention it is desirable that the screw driving tool be constructed as will be more fully hereinafter described.

The driving tool for the screw previously de scribed'is designated generally 22 and comprises a handle 24 from one end of which projects a shank 26. Formed at the end of the shank 2G remote from the handle 24 is a, bit 28 having opposite side face 30 lying in convergent planes as they recede from the shank 26. These faces 30 are flat so that at their convergent ends they form a relatively narrow edge which is adapted to enter the slot in the screw head l4. Extending outwardly from one face 30 of the bit 28 at its convergent end is a lip 32 which as illustrated in Figure 2 is adapted to engage in an undercut l8 of the slot or groove in the screw head in order to hold the screw in substantial alignment with the shank 26, and thereby facilitate the entrance of the screw into the work as suggested in Figure 1. Formed on the face 3!] remote from that from which the lip 32 extends is a longitudinally extending stop rib 34 which terminates at its end remote from the shank 26 in a plane with the end of the bit 23 and is adapted to enter one of the recesses 20 in the screw head M to prevent the screw from sliding transversely with respect to the bit while it is being inserted into the work. Obviously the undercut portion l8 of the slot or groove in the screw head may take the form of a dovetail with the lip 32 engaging one side wall of the slot adjacent the bottom l6 thereof while the opposite side wall of the slot engages the face 30 of the bit 28 remote from that carrying the lip 32.

In this way the screw will be held in Substantial alignment with the shank 26 and with the In use the screw is mounted on the driving I tool as suggested in the drawings and previouslyi,

described and when ing'this position it may be advanced toward the work as suggested in Fi ure 1 without requiring the use of both hands of the user to retain the screw and screw driver in proper assembled relation. Once the screw hasbeen driven home, the shank 26 and the bit 28 may be moved as suggested by the dotted lines in Figure 2 and the lip 32 extracted from the slot in the head of the screw.

While in the foregoing there has been shown and described the preferred embodiment of this invention, it is to be understood that minor changes in the details of construction and arrangement of parts maybe resorted to without departing from the-spiritand scope of the invention as claimed. 7

Having described: the invention, what is claimed as new. is:

' 1. In combination a, screw or the like and a driving tool therefor; said screw including a threaded stem, a head at one end of the stem, said head having a groove extending transversely thereacrossand opening through the top thereof, said groove intersecting the axis ofthe stem with its bottom wall lying substantially perpendicular to said stem, the side walls of the groove being undercut as they approach the bottom of thegroove, said side walls having op posed concave recesses therein substantially midway between opposite ends thereof and the bottom ends of the recesses coinciding with the bottom of the groove; and a driving tool for said screw includinga shank, a bit on the shank, opposite faces of said bit being substantially flat and converging asthey recede from the shank, to form a relatively thin end edge, a lip on the bit extending laterally from one face thereof at the end remote from the shank, said lip being adapted to enter the undercut in one side wall of the groove in the screw head,- a convex stop on the bit extending longitudinally along the face thereof remote from that from which the lip projects and said stop being located substantially midway between opposite ends of the end edge of the bit for entrance into a concave recess in the screw head to hold the screw against longitudinal movement of the lip when the screw is mounted on the driving tool.

2. In the combination of a screw having a head with a kerf therein and a driving tool of the type including a bit that is substantially rectangular in transverse section and engageable in the kerf to effect rotation of the screw about its longitudinal axis; an improvement comprising one of the side walls defining the kerf bein undercut adjacent the bottom of the kerf, said bit having opposite side faces, a lip on one of "the side faces adjacent an end of the bit and which lip is complementary to the undercut side wall for preventing axial separation of the screw and the bit, the other of the side walls definin the kerf having a groove therein transverse to the bottom of; the kerf, and the other face of the bit having a rib thereon complementary to the groove for preventing lateral separation of the screw and the bit.

3. In the combination of a screw having a head with a kerf therein and a driving toolrof the type including a bit that is substantially rectangular in transverse section and engageable in the kerf to effect rotation of the screw about its longitudinal axis; an improvement comprising the side walls defining the kerf being undercut adjacent the bottom of the kerf, said bit having opposite side faces, a lip on one of the side faces adjacent an end of the bit and which lip is complementary to the individual undercut side walls defining the kerf for preventing axial separation of the screw and the bit when the lip is engaged with either of said side walls, each of the side walls having a groove therein trans"- verse to the bottom of the kerf, and the other face of the bit having, a rib thereon compleinentary to the individual grooves, said lip being engageable' with one of the undercut side walls with the rib received in the groove in the other side wall to prevent both axial and lateral sepa ration of the screw and the bit.

MICHAEL DADERKO, SR. ROBERT A. LISELLA. JOHN DADERKO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 101,207 Angar Mar. 29, 1870 2,125,272 Erdman Aug. 2, 1938 

